U.S. Department of Health and Human Services

Bariatric Surgery

​​Definition and Facts for Bariatric Surgery
Bariatric surgery is an option if you have severe obesity and have not been able to lose enough weight to improve your health using other methods or have serious obesity-related health problems. The surgery makes the stomach smaller and sometimes changes the small intestine.
Types of Bariatric Surgery
In the United States, surgeons use three types of bariatric operations most often: gastric band, gastric bypass, and gastric sleeve. Surgeons use a fourth operation, duodenal switch, less often. Each type of surgery has advantages and disadvantages.
​​​​Bariatric Surgery Benefits
Bariatric surgery can improve many health problems related to obesity, such as type 2 diabetes, high blood pressure, unhealthy cholesterol levels, and sleep apnea. Surgery also may lead to improved physical function and mood, and better quality of life.
​​​​​Bariatric Surgery Side Effects
Bariatric surgery may cause side effects right after surgery or later. Side effects may include infection, diarrhea, nutritional shortages, gallstones, and hernias.
​​Potential Candidates of Bariatric Surgery
Bariatric surgery may be an option for adults and teens who have severe obesity and obesity-related health problems such as type 2 diabetes, sleep apnea, high blood pressure, or heart disease.
​​​Clinical Trials for Bariatric Surgery
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and other components of the National Institutes of Health (NIH) conduct and support basic and clinical research into many disorders.
Related Conditions and Diseases
Your Digestive System and How It Works

The digestive system is made up of the gastrointestinal (GI) tract-also called the digestive tract-and the liver, pancreas, and the gallbladder. The GI tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus​.​
Related Research

See more about obesity research at NIDDK.

This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings through its clearinghouses and education programs to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts. 

The NIDDK would like to thank:
Anita Courcoulas, M.D., M.P.H, University of Pittsburgh School of Medicine; Walter J. Pories, M.D., F.A.C.S., Brody School of Medicine, East Carolina University

This information is not copyrighted. The NIDDK encourages people to share this content freely.​​​​​​